ZnIn2S4 nanopowder as an efficient visible light-driven photocatalyst in the reduction of aqueous Cr(VI)

ZnIn2S4 nanopowder was synthesized via a facile hydrothermal method using Zn(CH3COO)(2)center dot 2H(2)O, InCl3 center dot 4H(2)O and thioacetamide as the reactants, and characterized by X-ray diffraction, transmission electron microscopy. N-2 adsorption and UV-Vis diffuse reflectance spectrum. The photocatalytic property of the as-synthesized ZnIn2S4 nanopowder was tested for the first time by the reduction of aqueous Cr(VI) under visible light (lambda>420 nm) irradiation, and compared with those of In2S3, ZnS and P25 TiO2. It was found that the as-synthesized ZnIn2S4 nanopowder was much more efficient than In2S3. ZnS and P25 TiO2 in the photocatalytic reduction of aqueous Cr(VI). Moreover, X-ray photoelectron spectroscopy analysis revealed that Cr(VI) was reduced to Cr(III) by ZnIn2S4-mediated photocatalysis. (C) 2012 Elsevier B.V. All rights reserved.